package com.yand.thinkingInJava.thinkingInJava21.ShareResource;


import java.util.Random;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

class Accessor implements Runnable{

    private final int id;
    public Accessor(int idn){
        id = idn;
    }

    @Override
    public void run() {
        while(!Thread.currentThread().isInterrupted()){
            ThreadLocalVariableHolder.increment();
            System.out.println(this);
            Thread.yield();
        }
    }

    public String toString(){


        return "#"+id+": "+ ThreadLocalVariableHolder.get();
    }

}







/**
 * 线程局部变量每一个线程之间互不干扰
 */
public class ThreadLocalVariableHolder {
    private static ThreadLocal<Integer> value = new ThreadLocal<Integer>(){
        private Random rand = new Random(47);

        protected synchronized Integer initialValue(){
            return rand.nextInt(10000);
        }
    };

    public static void increment(){
        value.set(value.get() + 1);
    }

    public static int get(){
        return value.get();
    }

    public static void main(String [] args){
        ExecutorService exec = Executors.newCachedThreadPool();
        for(int i = 0 ; i<5; i++){
           exec.execute(new Accessor(i));
        }

        try {
            TimeUnit.SECONDS.sleep(3);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        exec.shutdown();



    }




















}
